Mosquitoes are a world-wide nuisance and health hazard to humans and other animals. In the United States the mosquito is an important vector for a number of different viral diseases, including encephalitides. As there is currently no efficient means for the eradication of the mosquito, the identification of new strategies for mosquito control is clearly dependent on a better understanding of the biochemical and genetic basis for mosquito development. In this proposed study, the expression and potential role of hexameric serum proteins in the completion of metamorphosis and the establishment of adult fertility will be examined in the yellow fever mosquito, Andes aegypti. In holometabolous insects such as the mosquito, a set of highly abundant hemolymph proteins termed hexamerins or hexameric serum proteins (SPs) is primarily synthesized during the last stage of larval development. Proposed roles for hexamerins during metamorphosis include amino acid storage for elaboration of adult structures, maturation of the adult cuticle and serum transport of lipophilic macromolecules. Absence of one dipteran hexmerin has been correlated with significantly reduced fertility. To date there is no published examination of hexameric SP expression in any mosquito species. The structure and fate of the Aedes hexameric SPs will be analyzed, with specific focus on subunit composition, post-transnational modification and tissue recapture during adult development. Following the isolation and characterization of clones for the Aedes SP genes, the DNA sequence and developmental profile of RNA synthesis will be determined. Expression of these mosquito SP genes in Drosophila will serve to map 1) functional domain of typical insect hexameric SP subunits and 2) transcriptional regulatory sequences underlying tissue-- and stage- specific activity of the Aedes LSP genes. The ability of cloned Aedes SP genes to rescue lethal Drosophila SP mutants will be examined as part of a larger study of the roles of hexameric SPs during insect metamorphosis.
